Income Taxes (Detail Textuals) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Operating Loss Carryforwards [Line Items]
Undistributed earnings of foreign subsidiaries	$ 12.9
Total net income tax payments	152.2us-gaap_IncomeTaxesPaidNet	122.9us-gaap_IncomeTaxesPaidNet	158.7us-gaap_IncomeTaxesPaidNet
Bonus depreciation allowance	50.00%
Estimated favorable IRC Section 481(a) adjustments	21.7
Estimate accelerated deductions, gross	16.9
State and Local Jurisdiction
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards related to state income taxes	$ 11.3

Represents gross amount of estimated accelerated deductions for assets as on date.

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The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income, net of any cash received during the current period as refunds for the overpayment of taxes.

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Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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Amount of undistributed earnings of foreign subsidiaries intended to be permanently reinvested outside the country of domicile.

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The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

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